Somethings that I noticed that are different now then before are the fact that their are less fish now in our area, how many leaves there are in water of our area of observation and the ducks have been gathering lower in the stream. It is colder than normal today and not many people are at the park yet.

I think that the ducks moved from their former position because the water has become too deep for them to stand on the shallow rocks to keep them in one place. I also think that the fish went away because the current was too fast. I think that if the water becomes warmer in one spot then the fish will swim to that spot.

If we put rocks in the former position of where the ducks were then they will move back because they can stand again.
If we slow the current but manipulating the rocks then the fish will come back to the testing area.
If we make the water warmer in one spot then the fish will swim to that spot.

Assigned journal
I think so environmental pressures that may be driving the natural selection in the ecosystem could be the temperature of the water and the speed at which its moving as the fish tend to stay in the shallower warmer and slower moving water.